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Started programming on a ZX spectrum in the 80's and have moved through Assembly, Turbo Pascal, C++, C#, Fortran. My main area of focus is engineering and scientific computing like numerical methods and 3D graphics.


Feb
15
revised Compute the inertial tensor and then solve the equation?
added 243 characters in body
Feb
15
answered Compute the inertial tensor and then solve the equation?
Feb
13
answered Given the radius and angle of a frictionless banked curve, is it possible to find centripetal force?
Feb
11
comment Torsional Spring and Euler angles
Is there an actual gimbal (three rotational joints) between the bodies, or only the springs? I am asking because, joints transmit forces also, but virtual rot. springs may not.
Feb
11
comment Torsional Spring and Euler angles
The jacobian for ZYX is $$ J = \hat{k} \dot{\varphi} + R_z(\varphi) \left( \hat{j} \dot{\psi} + R_y(\psi) \hat{i} \dot{\theta} \right) $$
Feb
10
comment How to get moment from angular momentum
The mass in included in $I_{zz}$. You have to use one or the other. Correction from before, $k= I_{zz} \omega^2$
Feb
10
comment How to get moment from angular momentum
The rotational stiffness is then $k = J_T \omega^2$ which is used to find the period of oscillation $t_{cycle}$ and $\omega = \frac{2 \pi}{t_{cycle}} $
Feb
10
answered How to compute the inertia tensor ${\bf{J}} _{\Omega}$ of a body of revolution
Feb
10
comment How to get moment from angular momentum
You never mentioned in the question that the body is rotating with simple harmonic motion. Thats an important detail. If you know the angular amplitude $\Theta$ then $${\rm max}(\ddot{\theta}) = \Theta \omega^2$$
Feb
10
comment Buoyancy force on a hung object
Eureka! Did you even search buoyancy before posting? Do a free body diagram and add the buoyancy force upwards.
Feb
10
answered How to get moment from angular momentum
Feb
10
answered Torsional Spring and Euler angles
Feb
10
comment Torsional Spring and Euler angles
A torsional spring generates a force at a distance and not a moment (only). It is important to keep both in context.
Feb
10
comment Why in analysis of coupled oscillator, restoring force for uncoupled condition is taken in account?
The only possible coupled motion is when one displaces $+x$ the other one $-x$. The spring length is thus $(+x)-(-x)=2x$
Feb
9
comment What would happen if Newton's Cradle was made of other geometrical objects rather than spheres?
It would be interested to see this with shapes with two possible impact points each. One being a pivot point and the other the corresponding percussion point. This is achieved if the distance to the center of mass equals the radius of gyration (like with hanging rings).
Feb
9
comment What would happen if Newton's Cradle was made of other geometrical objects rather than spheres?
Sphere do not rotate when impacted, but other shapes do. So instead of transferring linear velocity from one object to the next it will induce rotations.
Feb
9
answered Why in analysis of coupled oscillator, restoring force for uncoupled condition is taken in account?
Feb
9
comment Coriolis force in free fall: Directions?
But the earth is moving in a circle and your tangential speed starts to mismatch the ground as soon as you leave it.
Feb
8
answered Coriolis force in free fall: Directions?
Feb
8
comment Applying a Force on a non fix body
The eccentric force is going to translate the center of mass, and also rotate the body. The combined motion is a rotation about a 3rd point called the instant center of rotation.